Construction of the Rostov NPP. Accident at Rostov NPP

2024 Author: Howard Calhoun | [email protected]. Last modified: 2023-12-17 10:16

The launch of the Rostov nuclear power plant will be the first after the Chernobyl disaster. All these years, the nuclear power industry has been going through hard times. Initially, it was planned to launch the first unit of the power plant in the fall of 2000. This date was announced based on the results of the expert review of the NPP project by the Ministry of Natural Resources and Ecology of the Russian Federation.

Need for NPP

Rostov NPP is part of the unified energy system of the North Caucasus region. It supplies electricity to 11 constituent entities of Russia, where 17.7 million people live. Many studies organized in institutions and government agencies have shown that the construction of the Rostov NPP is economically and energetically profitable.

The importance of the industry is growing against the backdrop of a decline in blue fuel production, which is typical for the central and southern regions. The universal project for the construction of the Rostov NPP provides for the construction of a separate independent building for each power unit, in which the VVER-1000 nuclear reactor will be installed.

Power unit device

Each power unit consists of a reactor (B-320) and a turbine plant. The coolant is divided into two circuits:

• Radioactive. Includes reactor itself, main circulation pumps, steam generators, pressurizer.
• Non-radioactive. It includes a turbine plant, water intake, steam part of generators and all necessary connecting pipes.

Fuel for nuclear power plants is in the reactor core. It contains 163 assemblies that generate heat. Inside each tablet is placed U-235 (slightly enriched uranium oxide). It is covered with a shell of sealed zirconium alloy sleeves. In the primary circuit, the coolant is a solution of boric acid. Its basis is highly purified water under pressure of 16 MPa.

Water neutrons, which are used to transfer heat and slow down the process, made it possible to obtain the necessary temperature coefficient with the "-" sign in a nuclear reactor. He determined the stability of VVER-1000 and its ability to regulate automatically.

What's under the station?

In the area of the Rostov nuclear power plant, geology was studied to a depth of 12 kilometers. 2 main layers are revealed: crystalline and sedimentary. The first consists of rocks older than the Cambrian, with the inclusion of various tectonic formations and regional faults. The second is formed by Paleozoic, Mesozoic and Cenozoic rocks.

The foundation of all nuclear power plant facilities passes through loams and sands, and rests on the Maykop clay. The NPP construction area belongs to the whole block of the crystalline foundation. Recent studies have confirmed that the structure does not exhibittectonic activity over 300 million years.

The profile obtained by seismic acoustics corresponds to the subhorizontal arrangement of sedimentary rocks. Now the earth's crust in this place is moving at a speed of 0 … 4.5 mm per year. Studies of the concentration of certain substances in groundwater and air did not reveal tectonic faults.

Seismicity of the area

When studying the nearest and distant sources of serious tectonic phenomena, requirements for a design earthquake were created. Its strength is 5 points, and the frequency is once every 500 years. The standards and seismic properties of the existing rocks make it possible to classify this area as a zone of earthquakes with a magnitude of 6 points, which occur once every 5 and 10 thousand years.

Based on the received data, the seismic resistance is 1 point higher in the design. Project documentation calculations were made on the basis of a maximum earthquake with an intensity of 7 points.

Hydrogeological conditions

Geological exploration has determined the presence of 2 aquifers in the earth. The layer of water closest to the surface is ubiquitous in the area. Surveys have confirmed the depth of groundwater at the construction site is 0.2-18 m. Water analysis showed their high destructive effect on concrete and metals.

The second aquifer is located within the boundaries of the future object at depths from 6.8 to 39 m.on the negative side: the mineral content and the proportion of sulfates increased. Near the facility under construction there are no underground and open sources of drinking water, from which the supply of the population is taken. There are no reserves or opportunities for such use in the future.

Safety

The safety of the Rostov NPP is provided by a system of various barriers that prevent the possible spread of radioactive products. Protection scheme:

• Fuel structure. Its hard appearance and defined structure keeps dangerous products from spreading.
• Zirconium sealed flasks containing pelleted uranium.
• Sealed walls of primary circuit pipes with prepared aqueous solution and other equipment.
• Accident localization system, which consists of a protective hermetic shell and a sprinkler system. This barrier includes a heavy structure with airtight locks for the passage of people, delivery of goods and other equipment.

Everything that interacts with radioactive substances is inside the containment. It is designed and built to withstand a variety of external impacts: 7-point maximum design earthquake, tornado, hurricane, shock waves.

Protection against environmental radiation is also provided by separate sewerage systems, water cooling, etc. Liquid waste processing and solid waste incineration are carried out on the territory of the station. Spent fuel is kept in special pools infor a three-year period and is exported in special containers by rail.

Number of power units

The capacity of the Rostov NPP is determined by the sum of the indicators of individual power units. The first and second of them produce 1 GW of electricity each. It turns out that at the moment the power of the nuclear power plant is 2 GW. In 2001 and 2010 the first and second power units of the Rostov nuclear power plant were put into operation.

Startup of unit 3 of the Rostov NPP took place in November 2014, and its inclusion in the unified energy system took place in December. Its capacity is planned to be sent to the Crimea, which is experiencing a lack of electricity.

In February-March, power unit No. 3 of the Rostov NPP was shut down for scheduled preventive maintenance. They were conducted in the department with turbines and the reactor, as well as in all shops. These works are a necessary stage in preparing the station for bringing it to its design capacity.

The construction of the fourth unit of the Rostov nuclear power plant is in full swing. At the moment, readiness exceeds 50%. Power unit No. 4 of the Rostov NPP is scheduled to be launched in 2017

Accident at the Rostov NPP

August 6, 2014, during construction work at the 3rd power unit of the Rostov NPP, an emergency occurred: a fall on the turbine from the boom of a carriage crane.

A commission has been set up to investigate the causes of the incident and find those responsible. Turbine inspection carried outunit showed that it was not damaged. What happened will not affect the terms of delivery of the object.

On the morning of November 4, 2014, residents of some towns and cities in the southern districts of the Rostov region experienced interruptions in the supply of electricity. The problems were felt by the population of the entire North Caucasian region. The light went out in the homes of almost 2 million people.

The reasons for the incident were later revealed. Work was underway on the southern line. At a certain moment, the automation disconnected the first and second power units of the nuclear power plant from the network. In a short time, power was supplied through emergency transmission lines.

The incident had no effect on the radiation background of the region (all indicators are within normal limits), there are no reasons for public concern.